Excavations continue in the Regio IX area of Pompeii (see post below). Recently, the discovery of a painted blue room was announced. Along with the frescoes painted on the walls, intact amphorae were uncovered. Numerous oyster shells were also unearthed. These shells were thought to have been used as part of the plaster or mortar mixture.
https://www.cnn.com/2024/06/04/science/blue-sacrarium-pompeii-excavation-scli-intl-scn/index.html